title: Urine erythropoietin level is associated with kidney and brain injury in critically ill neonates.
abstract: BACKGROUND
  Erythropoietin (EPO) is a glycoprotein hormone produced predominantly in the kidneys. The protective effect of exogenous EPO in hypoxic-ischemic brain injury has been thoroughly examined in neonates. However, the metabolism of endogenous EPO in neonates remains unclear.
  
  
  OBJECTIVE
  We aimed to evaluate the concentration of urinary EPO (uEPO) in critically ill neonates and to identify possible clinical and laboratory variables that may be associated with uEPO levels.
  
  
  METHODS
  The concentrations of EPO, cystatin-C, microalbumin, and α1-microglobulin in the first available urine sample during the initial 72 h of life were measured in 103 critically ill neonates. Clinical and laboratory data were collected for each neonate.
  
  
  RESULTS
  There was a positive correlation between uEPO levels and urinary levels of cystatin-C (r = 0.265, p = 0.008), microalbumin (r = 0.422, p < 0.001), and α1-microglobulin (r = 0.421, p < 0.001). The concentration of uEPO was elevated in neonates who developed acute kidney injury (AKI) during the first week of life compared with those without AKI (p = 0.002) and was also elevated in neonates with brain injury, as demonstrated by ultrasound or magnetic resonance imaging, compared to neonates without brain injury (p = 0.008). An increased log10 uEPO level was associated with the occurrence of AKI (OR 2.70, p = 0.007) and brain injury (OR 2.33, p = 0.016).
  
  
  CONCLUSIONS
  An increased urinary EPO level in the early postnatal period is significantly associated with kidney and brain injury in critically ill neonates.
authors.affiliation: Institute of Pediatric Research, Suzhou, China.
authors.forename: Yanhong
authors.initials: Y
authors.lastname: Li
authors.forename: Zhihui
authors.initials: Z
authors.lastname: Xiao
authors.forename: Jie
authors.initials: J
authors.lastname: Yan
authors.forename: Xiaozhong
authors.initials: X
authors.lastname: Li
authors.forename: Qing
authors.initials: Q
authors.lastname: Wang
authors.forename: Hong
authors.initials: H
authors.lastname: Zhu
authors.forename: Jian
authors.initials: J
authors.lastname: Pan
authors.forename: Xueming
authors.initials: X
authors.lastname: Zhu
authors.forename: Jian
authors.initials: J
authors.lastname: Wang
authors.forename: Xing
authors.initials: X
authors.lastname: Feng
mesh_terms: D058186:Acute Kidney Injury / Q000175:diagnosis / Q000652:urine*; D000419:Albuminuria / Q000652:urine; D000510:Alpha-Globulins / Q000652:urine; D015415:Biomarkers / Q000652:urine; D001930:Brain Injuries / Q000175:diagnosis / Q000652:urine*; D016638:Critical Illness; D055316:Cystatin C / Q000652:urine; D004921:Erythropoietin / Q000652:urine*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D016014:Linear Models; D016015:Logistic Models; D008279:Magnetic Resonance Imaging; D008297:Male; D015999:Multivariate Analysis; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011379:Prognosis; D012307:Risk Factors; D013997:Time Factors; D017585:Ultrasonography, Doppler, Transcranial; D015854:Up-Regulation
chemical_list: D000510:Alpha-Globulins; D015415:Biomarkers; C525030:CST3 protein, human; D055316:Cystatin C; C554270:EPO protein, human; C016001:alpha-1-microglobulin; D004921:Erythropoietin